This invention relates to an apparatus for writing information on X ray films. More particularly, this invention relates to an apparatus for writing patient identifying information on X-ray films, with the amount of exposure being properly corrected in accordance with the specific type of X-ray film used.
In order to handle a huge volume of X-ray films taken for many patients, a digital system for storing information in magnetic disks or other media is being developed in the medical field. This offers the advantages of reduced storage space and enabling quick access to the stored information.
Most of the X-ray films handled today have labels attached thereto for indicating the information on individual patients and such patient identifying information is entered as data into computers such as personal computers by authorized operators. This is a separate job from the task of digitizing the image information on X-ray films. Thus, the handling of X-ray films requires at least three operators, one who develops and performs subsequent processing of X-ray films, another who enters patient identifying information as input data, and the third operator who supplies a digitizer with image information specific to the body of a patient.
If patient identifying information that is written on X-ray films either before or after X-ray imaging, can be read and stored simultaneously with the reading of image information specific to the body of an individual patient, then separate personnel for entering the patient identifying information as input data is unnecessary and yet rapid and reliable processing of X-ray films can be accomplished.
In order to insure correct diagnosis, it is common practice in the medical field to perform selective use of X-ray films that have photographic characteristics as appropriate for the specific site of the patient's body. In other words, medical X-ray films are designed in such a way that they have characteristic curves and a sensitivity appropriate for the specific use. On the other hand, patient identifying information is conventionally written on X-rays with a constant amount of exposure. Therefore, the density of patient identifying information often varies from one X-ray film to another. In some X-ray films, the density of such information is too low, and in others, the density is so high that bleeding occasionally occurs which makes correct reading of the information practically impossible.